Conceptual artist Michael Craig-Martin—who taught Damien Hirst, Gary Hume, and others at London's Goldsmiths College in the 1970s—is often called the godfather of the Young British Artists. His early work referenced Minimalism and Dada's depiction of mass-produced objects. These objects form Craig-Martin's most recognizable works, paintings in which about 200 familiar items (eyeglasses, milk bottles, scissors) are depicted both realistically and graphically, represented in lurid, unexpected color combinations and black outline. The seminal piece An Oak Tree (1973) consists of a glass of water on a shelf, paired with text declaring that the glass is, in fact, an oak tree